North Korea fired three-short range rockets off its east coast on Thursday, South Korea’s Ministry of Defense said.

North Korea fired three-short range rockets off its east coast on Thursday, South Korea's Ministry of Defense said.

The last weapon was fired from the port city of Wonsan 35 minutes before Pope Francis arrived at an air base in Seoul.

The rockets were presumed to have landed in the East Sea after flying some 220 kilometers, South Korea's Joint Chiefs of Staff spokesman Um Hyo-sik told reporters, noting that Pyongyang did not impose a no-fly, no-sail zone ahead of the launch.

"Our military has maintained vigilance against additional launches and is taking necessary steps," Um added.

South Korea and the United States are scheduled to begin military exercises on Monday that the two countries say are defensive in nature, Reuters reported.

"Given that the US and the puppet forces of South Korea continue staging nuclear war exercises against us in particular, we will take countermeasures for self-defense which will include missile launches, nuclear tests and all other programs," a statement carried by North Korean state media last Friday said.